MySQL每隔一小会不操作报错ERROR 2013 (HY000) Lost connection to MySQL server during query问题
连接OA的MySQL库发现每隔一小会不操作就报错如下：
mysql> select now(); +---------------------+ | now() | +---------------------+ | 2022-01-11 09:47:41 | +---------------------+ 1 row in set (0.00 sec) mysql> select now(); ERROR 2013 (HY000): Lost connection to MySQL server during query mysql> select now(); ERROR 2006 (HY000): MySQL server has gone away No connection. Trying to reconnect... Connection id: 453751 Current database: *** NONE *** +---------------------+ | now() | +---------------------+ | 2022-01-11 09:48:27 | +---------------------+ 1 row in set (0.00 sec)
实际上有两个参数如下：
interactive_timeout = 1800 ##交互式会话空闲超时时间(mysql工具、mysqldump等)
wait_timeout = 1800 ##非交互式会话空闲超时时间，mysql api程序,jdbc连接数据库等
查看数据库的这两个参数值（单位：s）：
mysql> show variables where Variable_name in ('interactive_timeout','wait_timeout');
+---------------------+-------+
| Variable_name | Value |
+---------------------+-------+
| interactive_timeout | 30 |
| wait_timeout | 30 |
+---------------------+-------+
2 rows in set (0.00 sec)
由于我是使用mysql数据库本身的命令行交互式客户端mysql，因此调整调整interactive_timeout的值即可。
通过调整interactive_timeout=10,30,60后，会话1连接进去不操作，会话2持续观察：
会话2：
mysql> show full processlist; +--------+------+---------------------+-------+---------+------+-------+-----------------------+ | Id | User | Host | db | Command | Time | State | Info | +--------+------+---------------------+-------+---------+------+-------+-----------------------+ | 2 | root | ::1:53493 | td_oa | Sleep | 1 | | NULL | | 41 | root | ::1:53566 | td_oa | Sleep | 28 | | NULL | | 45 | root | ::1:53574 | td_oa | Sleep | 20 | | NULL | | 1709 | root | ::1:56311 | td_oa | Sleep | 68 | | NULL | | 454546 | root | 192.168.1.188:54046 | NULL | Sleep | 7 | | NULL | | 454553 | root | 192.168.1.188:54048 | NULL | Query | 0 | init | show full processlist | +--------+------+---------------------+-------+---------+------+-------+-----------------------+ 6 rows in set (0.00 sec)